Enhanced Charge Carrier Mobility of Evaporated Sb2Se3 via Post‐Treatment for High‐Speed Photodetection

Abstract

AbstractBenefiting from excellent optoelectronic properties and facile fabrication, Sb2Se3‐based semiconductor devices have drawn great attention in the last decade; in particular, Sb2Se3‐based solar cells and photodetectors have demonstrated decent performance metrics. However, the current research on Sb2Se3 devices is mainly focused on material and device processing and optimization, and few studies have been conducted on charge transport, which is limiting the further development of Sb2Se3‐based devices. To address this issue, post‐treatment techniques are introduced and their influence on the charge carrier dynamics of Sb2Se3 thin films is fully investigated. The charge carrier mobility of evaporated Sb2Se3 thin films is increased by an order of magnitude from 0.02 to 0.4 cm2 V−1 s−1 after the Se post‐treatment. Based on the optimized Sb2Se3 thin films, ultra‐fast photodiodes are further developed and a record‐fast response of 37 ns is achieved. Prototypical devices also demonstrated great potential for high‐speed photodetection in practical applications.